glsl: Rework assignments with write_masks to have LHS chan count match RHS.

It turns out that most people new to this IR are surprised when an
assignment to (say) 3 components on the LHS takes 4 components on the
RHS.  It also makes for quite strange IR output:

(assign (constant bool (1)) (x) (var_ref color) (swiz x (var_ref v) ))
(assign (constant bool (1)) (y) (var_ref color) (swiz yy (var_ref v) ))
(assign (constant bool (1)) (z) (var_ref color) (swiz zzz (var_ref v) ))

But even worse, even we get it wrong, as shown by this line of our
current step(float, vec4):

(assign (constant bool (1)) (w)
	(var_ref t)
	(expression float b2f (expression bool >=
		    (swiz w (var_ref x))(var_ref edge))))

where we try to assign a float to the writemasked-out x channel and
don't supply anything for the actual w channel we're writing.  Drivers
right now just get lucky since ir_to_mesa spams the float value across
all the source channels of a vec4.

Instead, the RHS will now have a number of components equal to the
number of components actually being written.  Hopefully this confuses
everyone less, and it also makes codegen for a scalar target simpler.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

1 files changed, 37 insertions, 37 deletions

diff --git a/src/glsl/builtin_function.cpp b/src/glsl/builtin_function.cpp
index c904f4629f..5f9bbec2f0 100644
--- a/src/glsl/builtin_function.cpp
+++ b/src/glsl/builtin_function.cpp
@@ -1889,8 +1889,8 @@ static const char *builtin_noise2 =
    "\n"
    "      (assign (constant bool (1)) (x) (var_ref a) (expression float noise (var_ref p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec4 + (var_ref p) (constant vec4 (601.0 313.0 29.0 277.0)))))\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xx (var_ref b)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -1903,8 +1903,8 @@ static const char *builtin_noise2 =
    "\n"
    "      (assign (constant bool (1)) (x) (var_ref a) (expression float noise (var_ref p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec3 + (var_ref p) (constant vec3 (601.0 313.0 29.0)))))\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xx (var_ref b)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -1919,8 +1919,8 @@ static const char *builtin_noise2 =
    "\n"
    "      (assign (constant bool (1)) (x) (var_ref a) (expression float noise (var_ref p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec2 + (var_ref p) (constant vec2 (601.0 313.0)))))\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xx (var_ref b)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -1935,8 +1935,8 @@ static const char *builtin_noise2 =
    "\n"
    "      (assign (constant bool (1)) (x) (var_ref a) (expression float noise (var_ref p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression float + (var_ref p) (constant float (601.0)))))\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xx (var_ref b)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "))\n"
@@ -1956,9 +1956,9 @@ static const char *builtin_noise3 =
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec4 + (var_ref p) (constant vec4 (601.0 313.0 29.0 277.0)))))\n"
    "      (assign (constant bool (1)) (x) (var_ref c) (expression float noise (expression vec4 + (var_ref p) (constant vec4 (1559.0 113.0 1861.0 797.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xxx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xxx (var_ref b)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref t) (swiz xxx (var_ref c)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
+   "      (assign (constant bool (1)) (z) (var_ref t) (var_ref c))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -1974,9 +1974,9 @@ static const char *builtin_noise3 =
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec3 + (var_ref p) (constant vec3 (601.0 313.0 29.0)))))\n"
    "      (assign (constant bool (1)) (x) (var_ref c) (expression float noise (expression vec3 + (var_ref p) (constant vec3 (1559.0 113.0 1861.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xxx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xxx (var_ref b)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref t) (swiz xxx (var_ref c)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
+   "      (assign (constant bool (1)) (z) (var_ref t) (var_ref c))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -1992,9 +1992,9 @@ static const char *builtin_noise3 =
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression vec2 + (var_ref p) (constant vec2 (601.0 313.0)))))\n"
    "      (assign (constant bool (1)) (x) (var_ref c) (expression float noise (expression vec2 + (var_ref p) (constant vec2 (1559.0 113.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xxx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xxx (var_ref b)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref t) (swiz xxx (var_ref c)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
+   "      (assign (constant bool (1)) (z) (var_ref t) (var_ref c))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "\n"
@@ -2010,9 +2010,9 @@ static const char *builtin_noise3 =
    "      (assign (constant bool (1)) (x) (var_ref b) (expression float noise (expression float + (var_ref p) (constant float (601.0)))))\n"
    "      (assign (constant bool (1)) (x) (var_ref c) (expression float noise (expression float + (var_ref p) (constant float (1559.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref t) (swiz xxx (var_ref a)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref t) (swiz xxx (var_ref b)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref t) (swiz xxx (var_ref c)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref t) (var_ref a))\n"
+   "      (assign (constant bool (1)) (y) (var_ref t) (var_ref b))\n"
+   "      (assign (constant bool (1)) (z) (var_ref t) (var_ref c))\n"
    "      (return (var_ref t))\n"
    "    ))\n"
    "))\n"
@@ -2037,10 +2037,10 @@ static const char *builtin_noise4 =
    "      (assign (constant bool (1)) (x) (var_ref _z) (expression float noise(var_ref _p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref _w) (expression float noise(expression vec4 + (var_ref _p) (constant vec4 (601.0 313.0 29.0 277.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref _r) (swiz xxxx (var_ref _x)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref _r) (swiz xxxx (var_ref _y)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref _r) (swiz xxxx (var_ref _z)))\n"
-   "      (assign (constant bool (1)) (w) (var_ref _r) (swiz xxxx (var_ref _w)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref _r) (var_ref _x))\n"
+   "      (assign (constant bool (1)) (y) (var_ref _r) (var_ref _y))\n"
+   "      (assign (constant bool (1)) (z) (var_ref _r) (var_ref _z))\n"
+   "      (assign (constant bool (1)) (w) (var_ref _r) (var_ref _w))\n"
    "      (return (var_ref _r))\n"
    "    ))\n"
    "\n"
@@ -2061,10 +2061,10 @@ static const char *builtin_noise4 =
    "      (assign (constant bool (1)) (x) (var_ref _z) (expression float noise(var_ref _p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref _w) (expression float noise(expression vec3 + (var_ref _p) (constant vec3 (601.0 313.0 29.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref _r) (swiz xxxx (var_ref _x)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref _r) (swiz xxxx (var_ref _y)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref _r) (swiz xxxx (var_ref _z)))\n"
-   "      (assign (constant bool (1)) (w) (var_ref _r) (swiz xxxx (var_ref _w)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref _r) (var_ref _x))\n"
+   "      (assign (constant bool (1)) (y) (var_ref _r) (var_ref _y))\n"
+   "      (assign (constant bool (1)) (z) (var_ref _r) (var_ref _z))\n"
+   "      (assign (constant bool (1)) (w) (var_ref _r) (var_ref _w))\n"
    "      (return (var_ref _r))\n"
    "    ))\n"
    "\n"
@@ -2085,10 +2085,10 @@ static const char *builtin_noise4 =
    "      (assign (constant bool (1)) (x) (var_ref _z) (expression float noise(var_ref _p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref _w) (expression float noise(expression vec2 + (var_ref _p) (constant vec2 (601.0 313.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref _r) (swiz xxxx (var_ref _x)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref _r) (swiz xxxx (var_ref _y)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref _r) (swiz xxxx (var_ref _z)))\n"
-   "      (assign (constant bool (1)) (w) (var_ref _r) (swiz xxxx (var_ref _w)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref _r) (var_ref _x))\n"
+   "      (assign (constant bool (1)) (y) (var_ref _r) (var_ref _y))\n"
+   "      (assign (constant bool (1)) (z) (var_ref _r) (var_ref _z))\n"
+   "      (assign (constant bool (1)) (w) (var_ref _r) (var_ref _w))\n"
    "      (return (var_ref _r))\n"
    "    ))\n"
    "\n"
@@ -2102,17 +2102,17 @@ static const char *builtin_noise4 =
    "      (declare () vec4 _r)\n"
    "\n"
    "      (declare () float _p)\n"
-   "      (assign (constant bool (1)) (xy) (var_ref _p) (expression float + (var_ref p) (constant float (1559.0))) )\n"
+   "      (assign (constant bool (1)) (x) (var_ref _p) (expression float + (var_ref p) (constant float (1559.0))) )\n"
    "\n"
    "      (assign (constant bool (1)) (x) (var_ref _x) (expression float noise(var_ref p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref _y) (expression float noise(expression float + (var_ref p) (constant float (601.0 313.0 29.0 277.0)))))\n"
    "      (assign (constant bool (1)) (x) (var_ref _z) (expression float noise(var_ref _p)))\n"
    "      (assign (constant bool (1)) (x) (var_ref _w) (expression float noise(expression float + (var_ref _p) (constant float (601.0 313.0 29.0 277.0)))))\n"
    "\n"
-   "      (assign (constant bool (1)) (x) (var_ref _r) (swiz xxxx (var_ref _x)))\n"
-   "      (assign (constant bool (1)) (y) (var_ref _r) (swiz xxxx (var_ref _y)))\n"
-   "      (assign (constant bool (1)) (z) (var_ref _r) (swiz xxxx (var_ref _z)))\n"
-   "      (assign (constant bool (1)) (w) (var_ref _r) (swiz xxxx (var_ref _w)))\n"
+   "      (assign (constant bool (1)) (x) (var_ref _r) (var_ref _x))\n"
+   "      (assign (constant bool (1)) (y) (var_ref _r) (var_ref _y))\n"
+   "      (assign (constant bool (1)) (z) (var_ref _r) (var_ref _z))\n"
+   "      (assign (constant bool (1)) (w) (var_ref _r) (var_ref _w))\n"
    "      (return (var_ref _r))\n"
    "    ))\n"
    "))\n"